How to set MIDI thru for
your system

Select MIDI Thru if you want to change the routing of MIDI channels received
from your MIDI input driver. This can be useful if you have an inexpensive
or older controller that cannot send data on more than one channel. For
example, if your controller only sends data on channel 1 and you want
to hear or record your drums that are on channel 10 on your drum machine,
reroute Channel 1 to Channel 10 by setting Channel 10 in the list box
of Channel 1.

Modern synths and keyboards are pretty flexible, but if you can't set
up your channels any other way you can use QuickScore Elite's MIDI thru
feature to help you out.